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UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF

MVM

[Equipment] 900 point to point

Need to make a NLOS link over 10-11 miles. Guessing 900 is the only thing that's going to work, and Radio Mobile seems to confirm that.

My question is what equipment I need. Can I use two Trango M900-SU's, or will they not talk to each other? I really want something cheap.
prairiesky
join:2008-12-08
canada

prairiesky

Member

do a link analysis on ligowave, pdf it and put it up, we'll take a look at it first...

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF

MVM

Sorry for the quality of the PDF, but I need to keep my location off of this for the moment.

Inssomniak
The Glitch
Premium Member
join:2005-04-06
Cayuga, ON

Inssomniak to UHF

Premium Member

to UHF
Not gonna work dude...

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF

MVM

said by Inssomniak:

Not gonna work dude...

Why not? Please explain. The RX threshold looks ok. Obviously, I'm new to wireless internet.

davidg
Good Bye My Friend
MVM
join:2002-06-15
00000

davidg

MVM

your fresnel is not clear at all, unless you can get higher up on both ends it won't work. you are just asking for all sorts of multipath with those numbers. and you only leave 5db for fade, you want closer to 20 if you don't want it dropping every time a bird shits on the antenna.
LLigetfa
join:2006-05-15
Fort Frances, ON

LLigetfa to Inssomniak

Member

to Inssomniak
said by Inssomniak:

Not gonna work dude...

+1

Also the EIRP is illegal.

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF to davidg

MVM

to davidg
Crap.

I can get a little higher on both ends, but not much.

Looks like I'm probably out of luck. I was hoping to get internet at the remote location without a monthly fee, and satellite is the only option there
telegraph
join:2010-01-05
Greensboro, MD

telegraph

Member

you need at least 20' to 30' on both side or somehow get space on that hill to use as a repeater
prairiesky
join:2008-12-08
canada

prairiesky to UHF

Member

to UHF
also 900 NLOS *can* go through things like vegetation, not hills

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF to telegraph

MVM

to telegraph
said by telegraph:

you need at least 20' to 30' on both side or somehow get space on that hill to use as a repeater

10' more on both ends is doable, but can't get much more as my tower already has a lot of wind load on it. But if I'm above the max allowed EIRP, then not sure what's next other than ignore the power limit since it's in the ham band anyway.

There's a 2.4GHz WISP that's in the same direction (I), and 100' higher, but he swears there's no way it would work. I can clearly see his antenna from the roof of the building at W, no hills or vegetation in the way. He insists 2.4 will only go 7 miles. Without knowing his EIRP or the RX Sens of his equipment I guess I can't really dispute it, and even if I did, it won't do any good. By my estimation the path loss would leave me with a signal of around -88, but I'm making a whole lot of assumptions to calculate that.

I guess I'm on to looking for 3G broadband. No DSL available here, it's in the middle of nowhere.

Inssomniak
The Glitch
Premium Member
join:2005-04-06
Cayuga, ON

Inssomniak

Premium Member

said by UHF:

said by telegraph:

you need at least 20' to 30' on both side or somehow get space on that hill to use as a repeater

There's a 2.4GHz WISP that's in the same direction (I), and 100' higher, but he swears there's no way it would work. I can clearly see his antenna from the roof of the building at W, no hills or vegetation in the way. He insists 2.4 will only go 7 miles. Without knowing his EIRP or the RX Sens of his equipment I guess I can't really dispute it, and even if I did, it won't do any good. By my estimation the path loss would leave me with a signal of around -88, but I'm making a whole lot of assumptions to calculate that.

Assume Max EIRP for the band. 36dbm at his end.
Assume a 24 dbi grid at your end.
Assume a -74 RX sens at best modulation.(assuming 80211)

2.4ghz works out to much longer than 7 miles. I got a -67 with good LOS at 10 miles, with 36dbm EIRP and a 24dbi grid at the CPE. Post the ligowave path analysis and we can see if that goes
jim_p_price7
join:2005-10-28
Henryetta, OK

jim_p_price7 to UHF

Member

to UHF
said by UHF:

said by telegraph:

you need at least 20' to 30' on both side or somehow get space on that hill to use as a repeater

10' more on both ends is doable, but can't get much more as my tower already has a lot of wind load on it. But if I'm above the max allowed EIRP, then not sure what's next other than ignore the power limit since it's in the ham band anyway.

There's a 2.4GHz WISP that's in the same direction (I), and 100' higher, but he swears there's no way it would work. I can clearly see his antenna from the roof of the building at W, no hills or vegetation in the way. He insists 2.4 will only go 7 miles. Without knowing his EIRP or the RX Sens of his equipment I guess I can't really dispute it, and even if I did, it won't do any good. By my estimation the path loss would leave me with a signal of around -88, but I'm making a whole lot of assumptions to calculate that.

I guess I'm on to looking for 3G broadband. No DSL available here, it's in the middle of nowhere.

The WISP may have some hard and fast rules about distance limits designed to prevent himself from winding up with difficult to support marginal clients.

Perhaps if you offer to do all the legwork (research, buying your own gear) you might have a chance.

If you can do a site survey from your place with a CPE and show him that the signal is useable maybe he'll change his mind. But contact him first and explain that you'd be happy to take on the work and research, maybe ask him what he would consider a reasonable signal threshold for a "yes".

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF to Inssomniak

MVM

to Inssomniak
said by Inssomniak:

Assume Max EIRP for the band. 36dbm at his end.
Assume a 24 dbi grid at your end.
Assume a -74 RX sens at best modulation.(assuming 80211)

I was assuming 24dbm from the radio, 6dbi antenna gain on his end, and 18 on mine. That gets me to -76, possibly higher, so looks like it could work. There is absolutely nothing in between but air.
said by jim_p_price7:

The WISP may have some hard and fast rules about distance limits designed to prevent himself from winding up with difficult to support marginal clients.

Perhaps if you offer to do all the legwork (research, buying your own gear) you might have a chance.

Maybe. The guy really doesn't want to be in the wireless business anymore, and his RF guy left years ago. I work with RF everyday, but this wireless internet stuff, fresnel zones, etc, is new to me. I deal in high power RF, and did analog cellular and mobile radio systems back in the day. I'd be more than happy to do the legwork on it, but he just seems uninterested.
LLigetfa
join:2006-05-15
Fort Frances, ON

LLigetfa

Member

If the WISP doesn't want to make the shot work, try to get permission to hang your own radio on his tower and get him to provide the internet feed to it.
Hahausuck
Premium Member
join:2003-12-14

Hahausuck to UHF

Premium Member

to UHF
Doesn't look good at 900 bro.....

WHT
join:2010-03-26
Rosston, TX

WHT to UHF

Member

to UHF
said by UHF:

Without knowing his EIRP or the RX Sens of his equipment I guess I can't really dispute it, and even if I did, it won't do any good. By my estimation the path loss would leave me with a signal of around -88, but I'm making a whole lot of assumptions to calculate that.

You don't need to know his exact EIRP or RX sensitivity. You can genera,lly assume his TX EIRP will be close to the mac 36 dBm allowed and RX sensitivity around -93 if he's placing CPEs out to 7 miles. If the link prediction is -88 dBm, that is only 5 dB of margin, where typically you'll see WISPs use a 15 to 20 dB margin.

Looking at the Ligowave plot, I don't see this in your future.

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF

MVM

The ligowave plot is 100' lower than the 2.4 ghz link would be. I think the 2.4 would work, but I haven't ran it through ligowave or radio mobile since he's not interested in working with me. He's on a city water tower, so I can't put my own radio up there.

Also, speed isn't super critical. 500kbps would be fantastic. And if it goes out sometimes due to rain fade or bird poop, so be it. It's not a critical link, just something to kill the boredom and monotony when I have to be stuck in the middle of nowhere.
jcremin
join:2009-12-22
Siren, WI

jcremin

Member

said by UHF:

Also, speed isn't super critical. 500kbps would be fantastic. And if it goes out sometimes due to rain fade or bird poop, so be it. It's not a critical link, just something to kill the boredom and monotony when I have to be stuck in the middle of nowhere.

WISP's are usually hesitant even if that is what you tell them. Reason being is that many people will beg for service, claiming that they just want something better than dialup and it doesn't matter if it is slow or cuts out, but then once they get used to it working, they can be big pains in the a$$ every time it glitches and seem to forget what they said 6 months ago when it was installed. Also, having a customer with low signal on the tower will reduce the capacity of the entire tower, which is probably the main reason for the distance limit. He's probably just learned that is around the distance limit that has worked well for him.

It's a tough situation. I have some potential customers that I have turned away. There is a possibility they would have perfect signal and never have any problems, but then again I have been burned by it enough times before that I just don't have enough time in a day to be constantly troubleshooting those connections. I find that about 5% of my customers take up 80% of my time.
jim_p_price7
join:2005-10-28
Henryetta, OK

jim_p_price7 to UHF

Member

to UHF
said by UHF:

The ligowave plot is 100' lower than the 2.4 ghz link would be. I think the 2.4 would work, but I haven't ran it through ligowave or radio mobile since he's not interested in working with me. He's on a city water tower, so I can't put my own radio up there.

Also, speed isn't super critical. 500kbps would be fantastic. And if it goes out sometimes due to rain fade or bird poop, so be it. It's not a critical link, just something to kill the boredom and monotony when I have to be stuck in the middle of nowhere.

Have you considered becoming your own ISP? Your situation is what led me to start my own WISP.
LLigetfa
join:2006-05-15
Fort Frances, ON

LLigetfa to jcremin

Member

to jcremin
said by jcremin:

...many people will beg for service, claiming that they just want something better than dialup and it doesn't matter if it is slow or cuts out, but then once they get used to it working, they can be big pains in the a$$ every time it glitches and seem to forget what they said 6 months ago when it was installed...

Sounds like my neighbour... WISP hooked him up in Winter... come Spring the trees leafed out and the whining began. I told him he needed to cut down a few trees but all he would do is call the WISP and ream them out, refuse to pay his bill, etc.

One day he got a call from Bell offering to hook him up to DSL. DSL was not available but the call centre in India didn't know that. The neighbour told the WISP what he could do with their CPE (anatomically impossible) and waited for the Bell tech that never came. Having burned his bridge, he was back on dialup.

UHF
All static, all day, Forever
MVM
join:2002-05-24

UHF to jim_p_price7

MVM

to jim_p_price7
said by jim_p_price7:

Have you considered becoming your own ISP? Your situation is what led me to start my own WISP.

No. The town I live in has 4 broadband providers, they don't need a 5th. The location I want access at is literally in the middle of a cornfield 10 miles out of town. Within 4 miles there might be 20 houses, and there's terrain issues and lots of trees. I'm on top of a 100' hill with few trees. Add in the fact I have no money for start up, and being a WISP doesn't appeal to me at all.

I had a T1 at this location but due to situations beyond my control, I can't access it anymore. That could change at any time, but I was hoping for a wireless link as an alternate source. This is why I don't care that much about speed/reliability as I'll likely have the T1 available as well. The firewall sucks, and I'd like to be able to VPN into my home LAN which isn't allowed on the T1.